xref: /rk3399_rockchip-uboot/common/image-sig.c (revision 56518e71041fafdfd7af3a24f263b0a22efbeda9)
1 /*
2  * Copyright (c) 2013, Google Inc.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation; either version 2 of
7  * the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
17  * MA 02111-1307 USA
18  */
19 
20 #ifdef USE_HOSTCC
21 #include "mkimage.h"
22 #include <time.h>
23 #else
24 #include <common.h>
25 #include <malloc.h>
26 DECLARE_GLOBAL_DATA_PTR;
27 #endif /* !USE_HOSTCC*/
28 #include <errno.h>
29 #include <image.h>
30 
31 struct image_sig_algo image_sig_algos[] = {
32 };
33 
34 struct image_sig_algo *image_get_sig_algo(const char *name)
35 {
36 	int i;
37 
38 	for (i = 0; i < ARRAY_SIZE(image_sig_algos); i++) {
39 		if (!strcmp(image_sig_algos[i].name, name))
40 			return &image_sig_algos[i];
41 	}
42 
43 	return NULL;
44 }
45 
46 static int fit_image_setup_verify(struct image_sign_info *info,
47 		const void *fit, int noffset, int required_keynode,
48 		char **err_msgp)
49 {
50 	char *algo_name;
51 
52 	if (fit_image_hash_get_algo(fit, noffset, &algo_name)) {
53 		*err_msgp = "Can't get hash algo property";
54 		return -1;
55 	}
56 	memset(info, '\0', sizeof(*info));
57 	info->keyname = fdt_getprop(fit, noffset, "key-name-hint", NULL);
58 	info->fit = (void *)fit;
59 	info->node_offset = noffset;
60 	info->algo = image_get_sig_algo(algo_name);
61 	info->fdt_blob = gd_fdt_blob();
62 	info->required_keynode = required_keynode;
63 	printf("%s:%s", algo_name, info->keyname);
64 
65 	if (!info->algo) {
66 		*err_msgp = "Unknown signature algorithm";
67 		return -1;
68 	}
69 
70 	return 0;
71 }
72 
73 int fit_image_check_sig(const void *fit, int noffset, const void *data,
74 		size_t size, int required_keynode, char **err_msgp)
75 {
76 	struct image_sign_info info;
77 	struct image_region region;
78 	uint8_t *fit_value;
79 	int fit_value_len;
80 
81 	*err_msgp = NULL;
82 	if (fit_image_setup_verify(&info, fit, noffset, required_keynode,
83 				   err_msgp))
84 		return -1;
85 
86 	if (fit_image_hash_get_value(fit, noffset, &fit_value,
87 				     &fit_value_len)) {
88 		*err_msgp = "Can't get hash value property";
89 		return -1;
90 	}
91 
92 	region.data = data;
93 	region.size = size;
94 
95 	if (info.algo->verify(&info, &region, 1, fit_value, fit_value_len)) {
96 		*err_msgp = "Verification failed";
97 		return -1;
98 	}
99 
100 	return 0;
101 }
102 
103 static int fit_image_verify_sig(const void *fit, int image_noffset,
104 		const char *data, size_t size, const void *sig_blob,
105 		int sig_offset)
106 {
107 	int noffset;
108 	char *err_msg = "";
109 	int verified = 0;
110 	int ret;
111 
112 	/* Process all hash subnodes of the component image node */
113 	for (noffset = fdt_first_subnode(fit, image_noffset);
114 	     noffset >= 0;
115 	     noffset = fdt_next_subnode(fit, noffset)) {
116 		const char *name = fit_get_name(fit, noffset, NULL);
117 
118 		if (!strncmp(name, FIT_SIG_NODENAME,
119 			     strlen(FIT_SIG_NODENAME))) {
120 			ret = fit_image_check_sig(fit, noffset, data,
121 							size, -1, &err_msg);
122 			if (ret) {
123 				puts("- ");
124 			} else {
125 				puts("+ ");
126 				verified = 1;
127 				break;
128 			}
129 		}
130 	}
131 
132 	if (noffset == -FDT_ERR_TRUNCATED || noffset == -FDT_ERR_BADSTRUCTURE) {
133 		err_msg = "Corrupted or truncated tree";
134 		goto error;
135 	}
136 
137 	return verified ? 0 : -EPERM;
138 
139 error:
140 	printf(" error!\n%s for '%s' hash node in '%s' image node\n",
141 	       err_msg, fit_get_name(fit, noffset, NULL),
142 	       fit_get_name(fit, image_noffset, NULL));
143 	return -1;
144 }
145 
146 int fit_image_verify_required_sigs(const void *fit, int image_noffset,
147 		const char *data, size_t size, const void *sig_blob,
148 		int *no_sigsp)
149 {
150 	int verify_count = 0;
151 	int noffset;
152 	int sig_node;
153 
154 	/* Work out what we need to verify */
155 	*no_sigsp = 1;
156 	sig_node = fdt_subnode_offset(sig_blob, 0, FIT_SIG_NODENAME);
157 	if (sig_node < 0) {
158 		debug("%s: No signature node found: %s\n", __func__,
159 		      fdt_strerror(sig_node));
160 		return 0;
161 	}
162 
163 	for (noffset = fdt_first_subnode(sig_blob, sig_node);
164 	     noffset >= 0;
165 	     noffset = fdt_next_subnode(sig_blob, noffset)) {
166 		const char *required;
167 		int ret;
168 
169 		required = fdt_getprop(sig_blob, noffset, "required", NULL);
170 		if (!required || strcmp(required, "image"))
171 			continue;
172 		ret = fit_image_verify_sig(fit, image_noffset, data, size,
173 					sig_blob, noffset);
174 		if (ret) {
175 			printf("Failed to verify required signature '%s'\n",
176 			       fit_get_name(sig_blob, noffset, NULL));
177 			return ret;
178 		}
179 		verify_count++;
180 	}
181 
182 	if (verify_count)
183 		*no_sigsp = 0;
184 
185 	return 0;
186 }
187